Check whether the PWR light flashes normally, if yes, please check whether the interface cable is properly connected; Whether the parameter configuration tool used is compatible. Related manuals and parameter configuration tools can be downloaded from www.usriot.com. Make sure PWR flashes, industrial modem and serial ports between computers are connected normally (for 232 interface modem, standard yellow test wire is connected to the second pin of modem, orange to the third pin, black to the tenth pin, the rest do not need to be connected; for 485 interface equipment, it needs to connect 485 to 232 converter to be connected to the computer), and the parameter configuration tool corresponding to the device is used. The baud rate for the V2X device is 57600 bps, and the default baud rate for the V3X device is 57600 bps. If the baud rate was modified before, please use the modified baud rate to connect. If the above checks are done, the configuration tools still can not be connected, please contact the technology support to troubleshoot:http://h.usriot.com.
RS232 RS485 Serial to GSM GPRS Modems USR-GPRS232-730
RS485 Industrial Cellular Modems | RS485 Serial GSM Modems USR-GPRS232-734